Relistor may weaken the GI wall

When to beware

As all meds do, mythylnaltrexone bromide (Relistor) has its share of possible side effects, the most common being dizziness, flatulence, mild diarrhea, nausea, stomach pain, vomiting, and hyperhidrosis. Severe reactions include a serious case of any already mentioned, or allergic reactions.

Today, Health Canada and Wyeth Canada added a new possible adverse reaction to the list: a heightened risk of gastrointestinal perforation, especially in those with GI cancers and other conditions that could weaken the gastrointestinal wall.

When Relistor came onto the scene – it was approved by Health Canada on March 28, 2008 – it relieved opioid-induced constipation in palliative-care patients with incurable cancers, end-stage COPD from emphysema, heart failure, Alzheimer’s disease, and so on, when other laxative therapies could not – in under 30 minutes. Administered by subcutaneous injection, it blocks opioids from entering cells, allowing bowels to revert to normal function, while not interfering with the opioid’s ability to relieve pain.

The current warning advises discontinuing Relistor and seeking professional help if severe, persistent symptoms like abdominal pain intensified by movement, nausea and vomiting -- possibly accompanied by fever and chills – worsen, as these can be signs of GI perforation.

It makes one wonder, though, if the original studies on this drug should have lasted a wee bit longer than four months.
Milena Katz

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